This invention relates generally to an image forming apparatus such as a copier with improved means for feeding OR removing original documents to be copied or discharging copy paper sheets which have been processed. In one aspect, the present invention relates more particularly to a copier capable of discharging copied original documents in a specified sequence. In another aspect, the present invention relates to an automatic document feeder capable of feeding a plurality of documents to a copier or the like such that they can be exposed to a copy lamp in a specified sequence. In still another aspect, the present invention relates to a copier capable of changing the sequence in which the processed sheets of copy paper are discharged.
With a conventional image forming apparatus such as a copier equipped with an automatic document feeder, documents to be copied are transported from a document supplying section such as a document tray to the exposure position on the document table in the order in which they are copied, and the documents removed from the document table are accordingly discharged onto a document discharge tray or the like in the same order in which they are copied. When a plurality of documents which form a set are copied, however, it is not always desirable or even convenient to copy them in the order of their page numbers. For improving the efficiency of the copying work, documents of the same size may be processed together independently of their page numbers. Likewise, documents to be enlarged with the same magnification may be lumped together and processed successively. In such a situation, discharged documents after they have been copied must be rearranged usually by hand into the original sequence. Not only is this a cumbersome job but documents are easily misarranged during such a manual operation.
With a conventional copier of the type considered above, processed sheets of copy paper are discharged either in the same order in which documents were copied or in the reverse order. If it is desired to obtain copies in an order different from the order in which the original documents are stacked, therefore, the order of discharged copy paper sheets must be changed or the order of the documents must be preliminarily changed. Either method is troublesome to execute.